This proposal requests funds to continue, beyond the 24th year, a program for training Ph.D. candidates in Cellular and Molecular Biology at New York University School of Medicine. This program involves investigators in seven basic science departments and training is offered in the general areas of structure, function and biogenesis of macromolecules, and subcellular organelles, as well as the mechanisms that regulate cell metabolism, differentiation and growth, and intercellular interactions during development. A major expansion in our faculty since the last renewal application adds to this program a very strong representation in several new areas at the cutting edge of Cell and Molecular Biology, including Structural Biology, Signal Transduction, Mechanisms, Developmental Genetics, Molecular Pathogenesis, and Cellular and Molecular Neurobiology. The interdisciplinary character of the program allows for a wider perspective for the student in approaching a research project and selecting thesis advisors. The design of the curriculum aims at providing the students with an advanced but balanced biological education with prepares them to understand and apply to their research sophisticated ideas and methodologies of biochemistry, genetics, immunology, and molecular cell biology. The increased visibility of the research enterprise at this Medical Center, as well as nationwide vigorous recruitment program implemented in the last three years, has more than doubled the number of applicants to the program who are eligible for grant support. The program consists of lecture courses, seminars and laboratory research and requires satisfactory performance in an oral and written qualifying examination. Students choose their thesis advisors and areas of research after completing three apprenticeships in different laboratories. Candidates for admission are selected by a committee of faculty members of the participating departments and their acceptance must be approved by the Sackler Institute, which administers all graduate programs in the Basic Medical Sciences at the School of Medicine. Graduate advisors guide the students in their choice of courses, research apprenticeships and selection of thesis advisors. Individual committees of faculty members follow the progress of students and advise them throughout the course of their thesis research. Normally, it is estimated that four to fie years will be required to obtain the Ph.D. degree.